Zapf’s spokesman, Job Nelson, said the councilwoman thinks there is some merit to the project given potential savings in building maintenance and leased office space but understands why many are struggling with the notion of building a new City Hall while cuts are threatened to public safety and other services.

“We’re kind of stuck in the middle of this one,” Nelson said. “I would say we side with the community and we need to fix the strong distrust they have before we can try.”

The project’s fate likely hangs on Zapf’s final decision.

The current plan calls for a 19-story City Hall totaling 576,000 square feet at C Street and First Avenue, where Golden Hall sits just west of the existing City Hall. It would include two levels of underground parking, a one-stop shop for city services on the first floor and a 400-seat City Council chambers. The rest of the building would be occupied by about 2,400 city office workers.

It’s a scaled-down version of the original proposal by Portland, Ore.-based Gerding Edlen for a 34-story structure with 1 million square feet.

City officials say the current 13-story building, which opened in 1965, is too small and will require $37 million in repairs over the next decade, at the end of which the structure would have to be replaced. The new building would allow the city to consolidate operations and eliminate about $13 million in annual lease payments at other downtown locations.

Much of that savings would then be used over the next 30 years to pay off the $320 million the city would need to borrow to finance the project. That total is higher than the construction estimate because of the cost of issuing bonds. An estimate from the council’s independent budget analyst said the total cost of the project would be about $613 million over three decades with interest and debt payments factored in.

Sanders said the city would have money left over after paying for the new building. He projects savings of about $24 million over the first 10 years and as much as $232 million during the building’s 50-year life cycle.

“It’s an option that we need to seriously consider,” he said.

Councilman Todd Gloria, who supports moving ahead without a public vote, said he knows voters would be hesitant to approve the project but that doesn’t stop the city from needing it.

“It’s not about just saving money today. We need to think about the future,” Gloria said.

Council President Tony Young, who sets the agenda, said he has not yet set a hearing date to revisit the issue but will address the proposed City Hall in a speech he plans to deliver next month.

The original timeline called for construction to begin in January 2012 with the goal of opening by July 2014.